Lens-grinding machine



May 20, 1924. V M 1,494,671

:sa spay LENS GRINDING MACHINE Filed Oct. 1. 1920 INVENTOR, GILBERT 5. DE) BY H114? 513,86 MM ATT6RNEY6 Patented May 20, 1924;

UNITED STATES 1,494,671 PATENT OFFICE.

GILBERT s. DEY, or ASOUTHBRIDGE, ASSACHUSETTS, assrenon TO AMERICAN or'rr- GAL comrnnxon sou'rnnnrnen, .MASSACHUSETTS; a VOLUN ARY AssocIaTIon or MASSACHUSETTS.

, rinns-eainnme MACHINE.

. Application filed October 1, 1920. I Serial No. 413,953.

To all whom it may concern.-

Be it known that I, GILBERT S. DEY, a citizen of the United States, residing at Southbridge, in the county of Worcester and State of Massachusetts, haveinvented certain new and useful Improvements in Lens- Grinding Machines, of which the following is a specification.

This invention relates to imp-rovements in grinding machinery and has particular reference to a novel and improved form of machine for use in the production of ophthalmic or similar high grade lenses.

Prior to my invention lenses have been produced through the use of a rotating member which may be either the tool or the lens block in combination with a loosely held opposed member. in this type of construction, however, due to the fact that the spinning of the opposed member, particularly if the same were a lens, would produce concentric rings or wave effects on the surface so that in the past it has been necessary to apply a breakup motion such as a transversely sliding action to said second member in order that satisfactory surfaces may be produced.

It is, therefore, the primary object of my present invention to produce a machine in which it will no longer be necessary to apply the additional power necessary for imparting movement to both of the parts, but in which the grinding movement may be applied to but one of the members, thus lessening the power required for the grinding operation, and in which the necessary break up movement to prevent the formation of the rings, wave effects or the like shall be automatically effected. I

Other objects and advantages of my improved construction should be readily apparent by reference to the following specification taken in connection with the accompanying drawings, and it will be understood that I may make any modifications in the specific details of construction shown and described within the. scope of the appended claims without departing from or exceeding thespirit of my invention.

Figure I represents a front elevation of a machine constructed in accordance with and embodying my improvements.

Figure II rep-resents a plan view thereof.

Difiiculty was experienced Figure III represents an enlarged detail view of the tool.

Figure IV represents a diagrammatic view of theline of grinding movement of the upper member in my machine generated through the use of my improvement.

In the drawings, the numeral 1 designates the main base or frame of the machine, having journaled therein the lower spindle 2 suitably driven as by the belt This spindle in ordinary use is provided on its upper end with the grinding tool 4 having a spherically curved surface to impart a contrageneric curve to the lenses. These lenses may be one or more in number as desired,

and are preferably carried as by the block 6 which is retained in position as by the angularly adjustable upper spindle 7 slidably I held as by the support 8 on the frame 9, and

provided at its upper end with the weightlO serving to urge the spindle and lens block in the direction of the grinding member. I

It has previously been customary to have i the frame 9 reciprocate carrying with it the pin or spindle 7 since in those instances where the pin or spindle has been stationary the driving of the grindingmember 4 while causing a spinningaction, producing grinding between the lenses and tool, would at the same time produce a plurality of concentric rings or wave surfaces.

My improvementin this form of grinding consists in forming centrally of the upper face of the lens block 6 the upstanding flange or collar portion 12, formed interiorly with the teeth 13 providing an interior gear surface with which meshes the teeth 14 of the drive pinion 15. This pinion is smaller by a number of teeth than the interior gear provided by the teeth 14 and has formed in its upper face the eccentrically disposed socket 16 adapted to receive the lower end ofthe pin 7.

Whereas in the former machine in the ab- I a direct spinning movement there Will be a spinning movement rolling around on the pinion 15 and at the same time an eccentric movement of the pinion and parts rolling around thereon, with the result that the relative movement of the center of the lens block in place of spinning on a point, Will be in the form of a continuous progressing trefoil form such as shown in Figure IV, or some variation thereof, a four, five or other point figure being producible by suitable relating of the eccentricity and relative numbers of teeth ofthe pinion and internal gear.

It will, therefore, be seen that I have provided an improved simplified grinding "ma chine, which having .a single grinding part and stationary opposed part, will through the form .of connection between the stationary member and the grinding member, cause the grinding member as it automatically spins though friction engagement with the grinding tool, to advance in a variable path, establishing a satisfactory break up movement, insuring perfect lens surfacesin place of merely spinningproducing wavy or defective surfaces, or instead of requiring ad ditional power suflicient to constantly shift the upper port-ion of the machine and in this manner prevent defective surfaces.

lVhile in the detailed description of the drawings I have particularly described'the member 4 as the grinding tool and the member 6 as the lens bearing block, it isto be understood the lenses 5 may be mounted on themember 4: and the member 6 maybe-the polisher without departing from my invention, but on the other hand with the production of extremely desirable results, the particular position of the parts being a matter of personal determination, varying in the form illustrated according to theshape of surface to be ground, although it will be understood that it is notentirely dependent on this'feature, since the block and grinding tool might be made of contragener-ic curve or the like if desired.

I claim: 7

1. A device of the character described including a rotated grinding member, a rotatable lens holding member in frictional ent stantially as and for the purpose described.

2. In combination with a rotated grinding member, a lens holding member having a socket, a connecting member having rolling engagement with the interior of the socket, and a stationary positioning device eccenr trically engaging the connecting member.

3. A machine of the character described including a rotated grinding member, an opposed rotatable lens holding member in frictional engagement therewith, said opposed member having an internal gear portion, a pinion of less size than the gear meshing therewith, and a stationary positioning device ecentrically engaging the pinion, substantially as and for the purpose described.

4. A machine of the character described including a rotatable grinding member, an opposed rotatable lens holding member in frictional engagement therewith, said op- {posed lens holding member having an internal gear portion, a pinion of less size than the gear meshing therewith, a positioning device -.e,ccentrically engaging the pinion,

and means for angnlarly adjusting the positioning member, substantially as and for the purpose described;

In testimony whereof I have affixed my signature, in presence of two Witnesses.

' GILBERT S. DEY.

.lVitnesses:

ALICE G. HASKELL, ESTHER M. LAFLER. 

